1. Technical Field of the Invention
The present invention relates to the manufacture of sautxc3xa9ed onion to be used as a raw material in cooking of, e.g., a hamburger, a croquette, soup or stew, and sofrit to be used as a raw material for a pasta sauce or the like (sofrit meaning, as exemplified by a sautxc3xa9ed food of a herb vegetable such as carrot, onion, celery, or the like, a sautxc3xa9ed food of vegetable containing onion insofar as the present invention is concerned). More particularly, the present invention relates to the manufacture of sautxc3xa9ed onion and sofrit which are superior in, inter alia, sweet taste and caramel flavor, have a good shape-retention property (i.e., a good shape-retainability), and can greatly improve the flavor of such food products as mentioned above. More particularly, the present invention relates to a sautxc3xa9ing machine (rotary sautxc3xa9ing machine) suitable for manufacture of the sautxc3xa9ed onion or the sofrit, a method for manufacturing the sautxc3xa9ed onion or the sofrit, and food products obtained by using the sautxc3xa9ed onion or the sofrit and having an excellent flavor quality.
2. Prior Art
As a method for manufacturing sautxc3xa9ed onion, there has been known, for example, xe2x80x9cMethod for Manufacturing Sautxc3xa9ed Onion and Food Productsxe2x80x9d disclosed in (1) Japanese Patent Application Laid-open No. 14352/2000.
And, in connection with this method (invention), it is described that xe2x80x9can object of the present invention is to provide a method for manufacturing sautxc3xa9ed onion which is excellent in sweet taste (i.e., sweetness), can suppress generation of a bitter taste (i.e., bitterness), an acrid taste (i.e., acridity) or an astringent taste, and can improve the flavor of curry or the like. Another object of the present invention is to provide a food product having a high flavor quality with the use of such sautxc3xa9ed onionxe2x80x9d based on the recognition of the prior art that xe2x80x9cit is known that sautxc3xa9ed onion is, in general, used as a vegetable basic ingredient when making curry or the like, whereby a spicy flavor is given to the resultant curry or the like. However, when onion is sautxc3xa9ed as a vegetable basic ingredient and, in particular on a commercial scale, there easily occurs the problem that the bitterness, the acridity or the astringent taste is produced in a final product, resulting from using cut raw onion.xe2x80x9d And xe2x80x9cthe present invention is based on such findings that onion can be brought into contact with the heat transfer surface of a sautxc3xa9ing machine without being piled up, whereby the temperature is increased in a short time, when the onion has been cut in such way that the resultant cut pieces have a specific volume and a flat-type pot is used as the sautxc3xa9ing machine, and furthermore, in this case, sautxc3xa9ed onion which is strong in sweetness and can suppress the bitterness and the like, can be manufactured, if the sautxc3xa9ing treatment is performed under the specific temperature and time conditionsxe2x80x9d (paragraphs 0002 to 0004 of the xe2x80x9cDetailed Description of the Inventionxe2x80x9d section in the above patent document).
xe2x80x9cThat is, the present invention is to provide a method for manufacturing sautxc3xa9ed onion by sautxc3xa9ing cut onion with the use of a sautxc3xa9ing machine, which method comprises the steps of: (a) cutting raw onion to such size that the resultant cut pieces have a volume of 0.02 to 8 cm3; (b) using a flat-type pot as the sautxc3xa9ing machine; (c) putting the onion immediately after cut into the sautxc3xa9ing machine, followed by increasing the temperature of the mass put within the sautxc3xa9ing machine to 90xc2x0 C. within 35 minutes, by the said 90xc2x0 C. being meant the 90xc2x0 C. when causing the temperature of the mass to reach the temperature described in the following (d) as being required for sautxc3xa9ing treatment of the onion after put into the sautxc3xa9ing machine; and (d) performing the sautxc3xa9ing treatment at a mass temperature of 90 to 102xc2x0 C. for 10 to 120 minutes. Furthermore, the present invention also provides a food product which has been produced by using the sautxc3xa9ed onion obtained by the above-mentioned manufacturing methodxe2x80x9d (paragraph 0005 thereof).
As has been described above, one of the essential characteristics of this method lies in the use of a flat-type pot as the sautxc3xa9ing machine, and in connection with the reasons for using the flat-type pot is described that xe2x80x9cthe cut onion is then sautxc3xa9ed with a sautxc3xa9ing machine. As the sautxc3xa9ing machine, a flat-type pot is used (one of the indispensable constituent features of the invention (b)). A shape of the flat-type pot is constituted by a bottom wall and side walls erected therearound substantially vertically, and in particular, a shape having a flat bottom wall or a fallen bottom wall and also having, for example, a flat central portion and a curved surface therearound or a curved surface on the entire surface is desirable. The heat transfer area of a flat-type pot (usually, the area of the bottom wall) is preferably 0.1 to 1.2 m2, and the cubic capacity (i.e., the volume) thereof is preferably approximately 0.01 to 0.5 m3. Using a flat-type pot having a wide heat transfer area can assuredly attain the temperature-elevating conditions of the sautxc3xa9ing processing of the later-described indispensable constituent feature (c). As the heat source for a flat-type pot is preferred a heat source which is of an electric type, an electromagnetic induction type, a direct heating type using the combustion of gas, a steam type provided with a jacket, or the like. Furthermore, a flat-type pot having an agitation function is preferablexe2x80x9d (paragraph 0007 thereof), and in Example 1 thereof was used a flat-type pot of a direct heating type and having agitation function in consistency therewith.
And, as to the application of the sautxc3xa9ed onion manufactured in the above manner, there is the description that xe2x80x9cthe sautxc3xa9ed onion manufactured by the method according to the present invention can be used for various kinds of Western-style boiled foods such as curry, hashed meat, stew and others or used for roux for cooking these foods (This may be a solid state, a liquid state or a paste state, or it may be diluted with water to be used for boiling or may be used for boiling without being diluted). It can be extensively used for various kinds of foods such as a variety of sauces, hamburgers or the like. In particular, in case of Western-style boiled foods or sauces, the use of the sautxc3xa9ed onion according to the present invention preferably provide a food with the high quality having a body taste or a mellow taste. The sautxc3xa9ed onion is also useful as a material ingredient on the commercial scalexe2x80x9d (paragraph 0012 thereof).
As is apparent from the above description, the aimed-at sautxc3xa9ed onion disclosed in the above-mentioned patent document (1) has no shape retention property or no shape retainability and, in consistency therewith, it is described that xe2x80x9cit is desirable that the sautxc3xa9ing processing is carried out in such a manner that the yield of the sautxc3xa9ed onion would be 25 to 75%. The sautxc3xa9ed onion may be cracked or finely crushed with a commit roll or a colloid millxe2x80x9d (paragraph 0011 thereof).
As a method for manufacturing sautxc3xa9ed onion, there has been also known xe2x80x9cMethod for Manufacturing Sautxc3xa9ed Onionxe2x80x9d disclosed in (2) Japanese Patent Application Laid-open No. 23633/2000.
This method (the invention) was achieved with the object similar to that of the method disclosed in the above-mentioned Japanese patent document (1), and on the basis of the recognition of the similar prior art as that described in the same Japanese patent document (1), and it is described in the Japanese patent document (2) that xe2x80x9cthe present invention is based on the findings that the above-described problem can be solved by cutting peeled raw onion into a predetermined shape, and effecting processing the cut onion under certain conditions followed by performing sautxc3xa9ing processing. That is, the present invention provides a method for manufacturing sautxc3xa9ed onion comprising the steps of: cutting peeled raw onion into a predetermined shape; bringing the cut onion in contact with 50 to 100 parts by weight of hot water per 100 parts by weight of the cut onion; and sautxc3xa9ing the resulting onion in the presence of 3 to 20 parts by weight of an edible oil at a mass temperature of 90 to 102xc2x0 C. for 70 to 170 minutes. Furthermore, the present invention provides also a method for manufacturing sautxc3xa9ed onion comprising the steps of: cutting peeled raw onion into a predetermined shape; immersing the cut onion in an edible oil having a temperature of 120 to 200xc2x0 C.; and throwing oil from the onion; followed by sautxc3xa9ing the resulting onion at a mass temperature of 90 to 102xc2x0 C. for 30 to 140 minutesxe2x80x9d (paragraph 0004 of the xe2x80x9cDetailed Description of the Inventionxe2x80x9d section of the above patent document).
To sum up, this method is characterized in that the peeled onion is first cut and xe2x80x9cthe cut pieces of onion are then (1) brought into contact with hot water and subjected to sautxc3xa9ing processing in the presence of an edible oil, or (2) subjected to immersing processing in an edible oil and thereafter to sautxc3xa9ing processingxe2x80x9d (paragraph 0005 thereof).
Moreover, as to a sautxc3xa9ing machine, xe2x80x9cit is preferable to carry out the sautxc3xa9ing processing in such manner that the yield of the sautxc3xa9ed onion would be 25 to 70%. It is desirable to perform sautxc3xa9ing with the use of a heating pot having an agitator, for example, a direct heating flat-type pot having an agitatorxe2x80x9d (paragraph 0007 thereof) and, in consistency with this, the direct heating flat-type pot having an agitator is used in all the examples.
And, as to the uses of the sautxc3xa9ed onion manufactured in the above-mentioned manner, there is the description that xe2x80x9cit is an object of the present invention to provide a method for manufacturing sautxc3xa9ed onion which can give an aromatic flavor to a product such as curry roux or the like and suppress an acrid taste or a bitter tastexe2x80x9d (paragraph 0003 thereof) and that xe2x80x9caccording to the present invention, xe2x80x9ca product such as curry roux or the likexe2x80x9d includes roux for curry, stew, hashed rice or the like (This may be a solid state, a liquid state or a gel state, or may be diluted with water to be used, or may be used without being diluted with water)xe2x80x9d (paragraph 0005 thereof).
As is apparent from the above description, the aimed-at sautxc3xa9ed onion disclosed in the above-mentioned patent document (2), does not have a shape retention property.
On the other hand, as a sautxc3xa9ing machine, there has been conventionally known a so-called rotary pot as compared with a flat-type pot.
As such a rotary pot, for example, there may be mentioned xe2x80x9cSautxc3xa9ing Machinexe2x80x9d disclosed in (3) Japanese Utility Model Application Laid-open No. 83323/1987. This sautxc3xa9ing machine has such structure that steam is not close therein. Specifically, a hot air blowing port is provided to the bottom of a rotary drum to cause the steam in the pot to escape therefrom, thereby improving the performance of the sautxc3xa9ing machine.
Additionally, in regard to a method of sautxc3xa9ing with the use of a rotary pot, there is known, e.g., xe2x80x9cSautxc3xa9-Cooking Method Using No Oilxe2x80x9d disclosed in (4) Japanese Patent Application Laid-open No. 146760/1988.
This method (the invention) relates to a method for sautxc3xa9ing foods such as onion or other vegetables, fruits or the like without using oil, namely, non-oil sautxc3xa9ing. And, the problems to be solved by the invention lies in that xe2x80x9csince the conventional sautxc3xa9-cooking with the use of oil provides an oil film protecting the material to be cooked, this cooking is very effective, but loses the moisture contained within the material to be cooked. Of course, this method can not be applied to foods which can not be adapted to fat. Further, the smell of an oil and fat content may disserve the original taste of a food and, on the other hand, the oil and fat content added to the food is oxidized by heating, whereby a peroxide value (POV) is increased which, in turn, leads to degeneration change in quality of a food. This is an obstacle for a long term preservationxe2x80x9d (the xe2x80x9c(c) Problems to be Solved by the Inventionxe2x80x9d column of the xe2x80x9cDetailed Description of the Inventionxe2x80x9d section of the above patent document), and in order to solve this problem, xe2x80x9cthe present invention provides a third heat-cooking means in addition to boiling and toasting, which can eliminate oils from the sautxc3xa9-cooking which has been considered as inseparable from oils and prevents oxidation by using only water. According to this means, moisture or water (or a solution including no oil and fat content, such as lecithin, fruit wine, alcohol or the like may be used instead) is supplied to and spread on an iron plate immediately before the object to be cooked is brought into contact with the iron plate which has been heated above a burning temperature, and the material to be cooked is moved and passed on the moisture film, whereby heat-cooking is effectedxe2x80x9d (the (d) Means for solving the Problemsxe2x80x9d column of the above patent document).
That is, this method (the invention) relates to xe2x80x9c(1) a sautxc3xa9-cooking method using no oil, wherein moisture or water is supplied to and spread on the surface of an iron plate to form a moisture film immediately before the object to be cooked is brought into contact with the iron plate which has been heated beyond a burning temperature, and the material to be cooked is slidingly passed on the moisture filmxe2x80x9d, and when such a sautxc3xa9-cooking method is carried out by using a rotary pot, this can be xe2x80x9c(2) a sautxc3xa9-cooking method using no oil as set forth in claim (1), wherein an agitator is provided to an inner side wall portion, a cylindrical rotary pot supported slantingly on a heating portion at a slat is rotated, and moisture is supplied to the heated inner wall surface immediately before the material to be cooked, when stirred up by the agitator, falls on the heated inner wall surfacexe2x80x9d (the xe2x80x9cWhat is claimed isxe2x80x9d section).
To sum up, the method disclosed in the patent document (4) is a method for manufacturing stirred sautxc3xa9s which do not have smell of an oil and can not get burned, in connection with the method according to the present invention which will be described later, and it can be said that this method is a rotary sautxc3xa9ing which forms a water film between an iron plate and an object to be heated, which is brought into contact therewith, which can decrease the POV and improve the flavor.
However, the onion obtained by this sautxc3xa9-cooking method using no oil has a pungent taste and is not preferable as sautxc3xa9ed onion or sofrit.
Another example of a method of sautxc3xa9ing with the use of a rotary pot is xe2x80x9cMethod for Manufacturing Half-processed Material to be cooked, Foodstuff and Apparatusxe2x80x9d disclosed in (5) Japanese Patent Application Laid-open No. 168348/1996. This relates to the improvements of the method disclosed in the patent document (4) referred to just above, and to a method for manufacturing a half-processed material to be cooked of onion, wild rocambole, cabbage, fruits, or the like, which half-processed material can be used as cooking basic ingredients for, e.g., a hamburger, a Chinese dumpling with minced pork and vegetable stuffing, a croquette or the like (paragraphs 0001 to 0002 of the xe2x80x9cDetailed Description of the Inventionxe2x80x9d section of the above patent document).
That is, there is described therein the problems that xe2x80x9csince a half-processed material to be cooked prepared by using a conventional non-oil sautxc3xa9ing method is subjected to sautxc3xa9ing processing by sliding a cut food material on the film of spread water on the moving heating surface, the mass temperature of the food material is low and therefore, a considerably long time is required by a sautxc3xa9ing film has been formed on the surfaces of the cut food material, during which the moisture (umami) in the food material exudes so that the original good taste of the food material is lost, and the yield at the time of completion of processing is deteriorated. Furthermore, since the mass temperature of the food material is low, whereas the temperature on the moving heating surface is high, a reverse osmotic pressure acts on the food material, and the moisture (umami) in the food material exudes to lose the flavor of the material in an extreme casexe2x80x9d (paragraphs 0005 and 0006 of the above patent document), and it is described that xe2x80x9cin view of the above-described problems, the present invention is intended to comply therewith in such manner that a food material is heated to such degree that the mass temperature of the food material itself is previously increased to approximately 40 to 80 degrees centigrade when performing non-oil sautxc3xa9ing, and then the food material is cut to a predetermined size followed by being supplied to the moving heating surface while maintained warm. Moreover, by cutting the food material while retaining the heat after preliminary heating, the mass temperature of the material to be processed can be increased in a short time during sautxc3xa9ing processing, and exudation of the umami taste can be prevented during the processing. In addition, deactivation of the enzyme is hastened so that crispness of the fresh material is maintained, meanwhile moisture can sufficiently penetrate in the material, thereby obtaining the sufficient sautxc3xa9ing effect without being scorched and the likexe2x80x9d (paragraphs 0007 to 0008 of the above patent document).
That is, this method (the invention) relates to xe2x80x9c(claim 1) a method for manufacturing a half-processed material to be cooked, wherein a material of a cooking foodstuff is heated in such degree that the mass temperature of the material itself is increased to 40 to 80 degrees centigrade and slided on the film of spread water on the moving heating surface while retaining heat, whereby sautxc3xa9-cooking is performedxe2x80x9d and, as an apparatus suitable for this method, there is mentionedxe2x80x9d (claim 4) an apparatus for manufacturing a half-processed material to be cooked, wherein the material to be cooked is sequentially carried into a rotary pot having an agitator on the heating surface from a heater through a heat retention cutting mechanismxe2x80x9d. Additionally, in the only example is also used a rotary pot having an agitator and a moisture spraying mechanism.
That is, there is described that xe2x80x9ca rotary pot 3 has an agitator 4 on the inner wall surface and swiveled by a rotary shaft 5, whereby a moving heating surface 6 is constituted, and a food material A subjected to cutting is supplied from the cutting mechanism 2 to this heating surface 6. When the cut food material A is supplied onto the moving heating surface 6, the material A moves by its own weight in a direction opposed to the moving direction of the heating surface 6 and is stirred up by the agitator 4. However, when the agitator 4 moves up beyond the support angle, the material A again falls on the heating surface 6. The material A is stirred up by the agitator 4, and moisture heated above 80 degrees centigrade is sprayed and supplied onto the part of the heating surface 6 on which part the material A does not exist, immediately before falling of the material A. The moisture is boiled and spread, whereby a film of the spread water W is formed between the falling material A and the heating surface 6. The food material A slides on the heating surface 6 without getting scorched by the film of spread water W and is again stirred up by the agitator 4. The spraying and supplying the moisture and the falling are repeated, during which deactivation of the enzyme in the food material and the sautxc3xa9-cooking are carried out in that period of timexe2x80x9d (paragraphs 0016 to 0019 of the above patent document), and that xe2x80x9csince the present invention has the above-described constitution, it is possible to assure such yield that the weight % of the food material is approximately 100% even after cooking, and improve the heat efficiency. Additionally, the process time can be shortened, which is useful for reduction in the production cost. Further, since the umami flavor or the moisture of the food material does not exudes but absorbed by the action of the osmotic pressure due to the mass temperature, it is possible to manufacture a half-processed material to be cooked maintaining the taste components or the flavor of the food material and crispness of the fresh materialxe2x80x9d (paragraphs 0022 to 0023 of the above patent document).
However, the half-processed onion obtained by the half-processed material to be cooked manufacturing method disclosed in the patent document (5) has also the pungent taste and is not preferable as sautxc3xa9ed onion or sofrit.
To sum up the prior art concerning the present invention, it is known that sautxc3xa9ed onion or sofrit is, in general, used as potherbs when making a hamburger, soup, a pasta sauce and others, which can add a sweet taste and an aromatic taste to the hamburger, the soup, the pasta sauce and others. However, when sautxc3xa9ing onion or a material for sofrit as the potherbs, in the sautxc3xa9-processing on the commercial scale in particular, problems are apt to occur that the pungent taste and the acrid taste remain in a final product, and the like, in sautxc3xa9ing with the use of a conventional rotary pot, and that the shape retention property can not be provided, the yield is the same as that of a stir-sautxc3xa9 obtained by using a rotary pot, the sweet taste and the caramel flavor are both decreased, and the like, by sautxc3xa9ing with the use of a flat-type pot.
[Problems to be Solved by the Invention]
In the background of the prior art described above, it is an object of the present invention to provide a method for manufacturing sautxc3xa9ed onion or sofrit which has a less pungent taste and a less acrid taste, is superior in the sweet taste and the caramel flavor and in the shape retention property, and can accordingly improve the flavor of hamburger, soup, pasta sauce and the like. Further, it is another object of the present invention to provide food products excellent in flavor quality using the thus manufactured sautxc3xa9ed onion or sofrit.
[Means to Solve the Problems]
As a result of their dedicated studies to achieve the above-mentioned objects, the present inventors have found, as regards sautxc3xa9ing onion or materials for sofrit, that a rotary sautxc3xa9ing machine, preferably a rotary sautxc3xa9ing machine equipped with an agitation blade having a specific shape is used as the sautxc3xa9ing machine; and concurrently therewith, an auxiliary heater such as overheated steam, steam, hot air or the like is used and/or oscillation is carried out, whereby the materials can be uniformly heated and increased in temperature in a short time, as chefs do using a frying pan (rapid rising of the initial mass temperature), and that sauted onion or sofrit which has a less pungent taste and a less acrid taste, is excellent in sweet taste and caramel flavor, and has a good shape retention property, can be manufactured by preventing burning by deglazing with the use of water spray, if required, in performing the subsequent sautxc3xa9ing processing. On the basis of these findings, the present inventors have completed the present invention.
Accordingly, the present invention relates to a rotary sautxc3xa9ing machine, wherein the cross-sectional shape of the surface in the rotating direction of a blade provided in the pot is such that, in a cross section vertical to the rotary shaft of the pot, assuming that a straight line running from an attachment point of the blade onto the cylindrical surface toward the center of the rotary shaft is an x coordinate axis, the attachment point is x=0 (the origin), and the position of the foot on the x axis of a perpendicular line extending downwards from an end of the blade is x=1, and when the height y of the cross-sectional line of the blade is expressed by a function of x, f(x), the x coordinate at which a value of the derived function of y=f(x) becomes 0 is not less than 0.4, and at the same time, the absolute value of the definite integral of the derived function between the position where the value of the derived function becomes 0 and x=1 is not more than 40% of the absolute value of the definite integral of the derived function until the derived function becomes 0 from x=0. Further, the present invention relates to a method for manufacturing sauted onion or sofrit, wherein a rotary sautxc3xa9ing machine is used as the sautxc3xa9ing machine when sautxc3xa9ing cut onion or materials for sofrit; and concurrently therewith, an auxiliary heater such as overheated steam, steam, hot air or the like is used and/or the rotary sautxc3xa9ing machine is oscillated, whereby the temperature at the center of a material piece in the rotary pot is increased to 85-95xc2x0 C. within 10 minutes; and after the temperature at the center of the material piece reaches 95xc2x0 C., deglazing is continuously carried out by spraying water, as required, while maintaining the surface temperature of the material piece at 95-120xc2x0 C. for 15 to 120 minutes, thereby effecting sautxc3xa9ing processing. Furthermore, the present invention relates to food products with a high flavor quality using therein sauted onion or sofrit obtained by the above-described manufacturing method.